B bIc@sdZddlmZmZmZddlmZddlmZdZ dZ ddl Z ddl Z dd l mZmZdd lmZdd lmZdd lTGd ddeZGdddeZGdddeZddZeiZedkrddlZddl Z ee jedS)a Module simtk.unit Contains classes Unit and ScaledUnit. This is part of the OpenMM molecular simulation toolkit originating from Simbios, the NIH National Center for Physics-Based Simulation of Biological Structures at Stanford, funded under the NIH Roadmap for Medical Research, grant U54 GM072970. See https://simtk.org. Portions copyright (c) 2012 Stanford University and the Authors. Authors: Christopher M. Bruns Contributors: Peter Eastman Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS, CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. )divisionprint_functionabsolute_import)iterkeys)rangezChristopher M. Brunsz0.5N)MyMatrixzeros) BaseDimension)BaseUnit)*c@seZdZdZdZddZddZddZd d Zd d Z d dZ ddZ ddZ ddZ ddZddZddZddZeZiZddZdd Zd!d"Zd#d$ZiZd%d&ZiZd'd(ZiZd)d*Zd+d,Zd-d.Zd/d0Z d1S)2Unitz0 Physical unit such as meter or ampere. dc Csxi|_i|_g|_x|D]~\}}|dkr.qt|tr|}|j}||jkrVi|j|<||j|krrd|j||<|j|||7<q|j||fqWi|_xD|jD]:}i|j|<x*|j|D]}|j|||j||<qWqWx~|jD]t\}} xj|D]^\} } | j}||jkr(i|j|<| |j|krFd|j|| <|j|| | | 7<qWqW|j dS)zCreate a new Unit. Parameters: - self (Unit) The newly created Unit. - base_or_scaled_units (dict) Keys are BaseUnits or ScaledUnits. Values are exponents (numbers). rN) _top_base_units_all_base_units _scaled_unitsitems isinstancer dimensionappenditer_base_unitssort) selfZbase_or_scaled_unitsZbase_or_scaled_unitpowerbudimdu scaled_unitZ exponent1 base_unit exponent2r!/lib/python3.7/site-packages/parmed/unit/unit.py__init__8s:        $z Unit.__init__c Cst|jdkstt|jdks$ttt|j}|j|}t|dksLttt|}||}t|j||}|} |dkrt |d|} | || t |di} | S)z Convenience method for creating a new simple unit from another simple unit. Both units must consist of a single BaseUnit. rrg?) lenrAssertionErrorrnextrr rmathpowZdefine_conversion_factor_tor ) rZscalenamesymbolrZbase_unit_dictZparent_base_unitZparent_exponentZ new_base_unitZ true_scalenew_unitr!r!r" create_unitcs    zUnit.create_unitccs`xZt|jD]H}d}x,t|j|D]}||j||7}q,W|dkr||fVqWdS)zO Yields (BaseDimension, exponent) tuples comprising this unit. rN)sortedrkeys)rrexponentrr!r!r"iter_base_dimensionsys zUnit.iter_base_dimensionsccsPxJt|jD]8}x2t|j|D]}|j||}||fVq(WqWdS)z Yields (BaseUnit, exponent) tuples comprising this unit, including those BaseUnits found within ScaledUnits. There might be multiple BaseUnits with the same dimension. N)r-rr.)rrrr/r!r!r"iter_all_base_unitsszUnit.iter_all_base_unitsccsPxJt|jD]8}x2t|j|D]}|j||}||fVq(WqWdS)zd Yields (BaseUnit, exponent) tuples in this Unit, excluding those within BaseUnits. N)r-rr.)rrunitr/r!r!r"iter_top_base_unitsszUnit.iter_top_base_unitsccs"x|jD]\}}||fVqWdS)N)r)rr2r/r!r!r"iter_scaled_unitsszUnit.iter_scaled_unitsccs4x|D] }|Vq Wx|D] }|Vq"WdS)N)r3r4)ritemr!r!r"iter_base_or_scaled_unitss zUnit.iter_base_or_scaled_unitscCs*d}x |jD]\}}||j|9}q W|S)z There may be ScaleUnit components to this Unit. Returns conversion factor to the set of BaseUnits returned by iter_all_base_units(). Units comprised of only BaseUnits return 1.0 g?)rfactor)rr7rr/r!r!r"#get_conversion_factor_to_base_unitssz(Unit.get_conversion_factor_to_base_unitscCst|s dS||kS)NF)is_unitget_name)rotherr!r!r"__eq__sz Unit.__eq__cCs || S)N)r<)rr;r!r!r"__ne__sz Unit.__ne__cCs&||std||f||dkS)zCompare two Units. Raises a TypeError if the units have different dimensions. Returns True if self < other, False otherwise. z+Unit "%s" is not compatible with Unit "%s".g?) is_compatible TypeErrorconversion_factor_to)rr;r!r!r"__lt__s z Unit.__lt__cCs0y|jStk rYnXt||_|jS)z6 Compute a hash code for this object. )_hashAttributeErrorhashr:)rr!r!r"__hash__s z Unit.__hash__cCs|t|dS)a+Divide a Unit by another object. Returns a composite Unit if other is another Unit. Returns a Quantity otherwise. UNLESS other is a Quantity AND the resulting unit type is dimensionless, in which case the underlying value type of the Quantity is returned. )r()rr;r!r!r" __truediv__s zUnit.__truediv__cCsr|tjkr(|tj|kr2tj||Sn itj|<i}x |D]\}}||||<q@Wt|}|tj||<|S)zhRaise a Unit to a power. Returns a new Unit with different exponents on the BaseUnits. )r _pow_cacher6)rr/resultr2r r+r!r!r"__pow__s  z Unit.__pow__c Csi}d}x2|D]&\}}|ddkr,d}P|d||<qW|si}i}xL|D]@\}}|j}||krz|||<|||<qR||}|||7<qRWx4|D](\}}|ddkrtd|d||<qWt|S)z Returns square root of a unit. Raises ArithmeticError if component exponents are not even. This behavior can be changed if you present a reasonable real life case to me. TrFz&Exponents in Unit.sqrt() must be even.)r6r1rrArithmeticErrorr ) rZ new_unitsZ nice_and_evenrr/Zbase_units_by_dimensionrrrr!r!r"sqrts,   z Unit.sqrtcCs|S)z,Returns the human-readable name of this unit)r:)rr!r!r"__str__sz Unit.__str__cCs.i}x|D]\}}|||<qWdt|S)z Returns a unit name (string) for this Unit, composed of its various BaseUnit symbols. e.g. 'kilogram meter**2 second**-1' zUnit(%s))r6repr)runitsr2rr!r!r"__repr__ s z Unit.__repr__cCs|tjkr&|tj|kr&tj||St|s>|r:dSdSi}x|D]\}}|||<qLWi}x|D]\}}|||<qnWt|t|krd}n||k}|tjkritj|<|tj||<|S)zf Returns True if two Units share the same dimension. Returns False otherwise. TF)r _is_compatible_cacher9is_dimensionlessr0r$)rr;Z self_dimsrr/ other_dimsrIr!r!r"r>-s(     zUnit.is_compatiblecCsN|tjkrtj|Sx*|D]\}}|dkrdtj|<dSqWdtj|<dS)zVReturns True if this Unit has no dimensions. Returns False otherwise. rFT)r _is_dimensionless_cacher0)rrr/r!r!r"rSKs    zUnit.is_dimensionlesscCs(d}||kr|S|tjkr6|tj|kr6tj||S||sDt||9}||}i}xN|D]B\}}|j}||kr|||kr|||||9}qj|||<qjWxN|D]B\}}|j}||kr|||kr|||||}q|||<qW|tjkritj|<|tj||<|S)a Returns conversion factor for computing all of the common dimensions between self and other from self base units to other base units. The two units need not share all of the same dimensions. In case they do not, the conversion factor applies only to the BaseUnits of self that correspond to different BaseUnits in other. This method requires strict compatibility between the two units. g?)r _conversion_factor_cacher>r%r8r1rr@)rr;r7Zcanonical_unitsr2rrr!r!r"r@[s4          zUnit.conversion_factor_tocCs ||S)a Returns a new Unit with the same dimensions as this one, expressed in a particular unit system. Strips off any ScaledUnits in the Unit, leaving only BaseUnits. Parameters - system: a dictionary of (BaseDimension, BaseUnit) pairs ) express_unit)rsystemr!r!r"in_unit_systems zUnit.in_unit_systemc Cs8d}d}d}xR|D]F\}}|dkr|d7}|dkr>|d7}||j7}|dkr|d|7}qWd}d}d}xX|D]L\}}|dkrv|d7}|dkr|d7}||j7}|dkrv|d| 7}d }qvWd|krd} nd|kr|rd |} nd |} d|krd} n|} d|kr|kr(nnd }n d | | f}|S)z Returns a unit symbol (string) for this Unit, composed of its various BaseUnit symbols. e.g. 'kg m**2 s**-1' rr g?z**%gTgFz/%sz/(%s) dimensionlessz%s%s)r6r*) rr*pos pos_countr2rneg neg_countsimple_denominator neg_string pos_stringr!r!r" get_symbolsF      zUnit.get_symbolc CsZy|jStk rYnXd}d}xR|D]F\}}|dkr.|d7}|dkrV|d7}||j7}|dkr.|d|7}q.Wd}d}d}xX|D]L\}}|dkr|d7}|dkr|d7}||j7}|dkr|d| 7}d }qWd|krd}n"d|kr|rd |}nd |}d|krd} n|} d|kr:|krDnnd } n d | |f} | |_| S)z Returns a unit name (string) for this Unit, composed of its various BaseUnit symbols. e.g. 'kilogram meter**2 secon**-1'. rZrrr g?z**%gTgFz/%sz/(%s)r\z%s%s)_namerCr6r)) rr]r^r2rr_r`rarbrcr)r!r!r"r:sN     z Unit.get_nameN)!__name__ __module__ __qualname____doc____array_priority__r#r,r0r1r3r4r6r8r<r=rArErGZ__div__rHrJrMrNrQrRr>rUrSrVr@rYrdr:r!r!r!r"r 1s<+      ' * -r c@sdeZdZdZdZddZddZddZd d Zd d Z d dZ ddZ ddZ ddZ ddZdS) ScaledUnitz ScaledUnit is like a BaseUnit, but it is based on another Unit. ScaledUnit and BaseUnit are both used in the internals of Unit. They should only be used during the construction of Units. rc Cs||_i}x`|D]T\}}|j}||kr8||g||<q||d|7<|j||d|9_qWx(|D]\} }|j| j|9_qvW||_||_||_||_dS)Nrr) r7r1rr@r4 base_unitsmasterr)r*) rr7rmr)r*rlrr/rZsbur!r!r"r#s zScaledUnit.__init__ccs(x"t|jD]}|j|VqWdS)N)r-rlr.)rrr!r!r"__iter__ szScaledUnit.__iter__ccs x|D]\}}||fVqWdS)Nr!)rrr/r!r!r"rszScaledUnit.iter_base_unitsccs*x$|D]\}}|dkr|j|fVqWdS)zs Returns a sorted tuple of (BaseDimension, exponent) pairs, describing the dimension of this unit. rN)r)rrr/r!r!r"r0szScaledUnit.iter_base_dimensionscCst|}|t|S)zr Returns a sorted tuple of (BaseDimension, exponent) pairs, that can be used as a dictionary key. )listr0rtuple)rlr!r!r"get_dimension_tuples zScaledUnit.get_dimension_tuplecCs|jS)N)r7)rr!r!r"r8"sz.ScaledUnit.get_conversion_factor_to_base_unitscCs^||kr dSi}x|D]\}}|||<qWt|tr>|}n t|di}|jt||S)Ng?)rrr r7r@)rr;rrr/Zother_ur!r!r"r@%s   zScaledUnit.conversion_factor_tocCst|t|kS)z!Compare two ScaledUnits. )rD)rr;r!r!r"rA2szScaledUnit.__lt__cCs|jS)z:Returns a string with the name of this ScaledUnit )r))rr!r!r"rN7szScaledUnit.__str__cCszd}x8|D],\}}t|dkr*|d7}|d||f7}qWdt|jdt|jdt|jdt|jd S) z rZrz, z%s: %dzScaledUnit(factor=z , master=z, name=z , symbol=))rr$rOr7strrmr)r*)rrlrrr!r!r"rQ<s  zScaledUnit.__repr__N)rfrgrhrirjr#rnrr0rrr8r@rArNrQr!r!r!r"rks rkc@s0eZdZdZddZddZddZdd Zd S) UnitSystemz A complete system of units defining the *base* unit in each dimension Parameters ---------- units: ``list`` List of base units from which to construct the unit system c CsN||_i|_i}x:|jD]0}x*|D]\}}|j}||kr&|||<q&WqW||_t|jt|jksntdt|}| i|_ x"t t|D]}||j ||<qWt t|j}xLt t|jD]:} |j| }x*| D]\} } |j | } | || | <qWqWy ||_Wn4tk rH} ztdt| Wdd} ~ XYnXdS)Nz>> is_unit(16) False )rr )xr!r!r"r9s r9__main__)riZ __future__rrrZparmed.utils.sixrZparmed.utils.six.movesr __author__ __version__r'sysZmymatrixrr Z basedimensionr Zbaseunitr Zstandard_dimensionsobjectr rkrur9r\rfZdoctestZtestmodmodulesr!r!r!r"!s,    AY]